Rest equivalent width (W₀) as a function of the impact parameter (b) obtained from the line profiles in Fig. 5, corresponding to the foreground composite spectra (0 kpc) and the background composite spectra at ⟨b⟩  =  68.6 kpc (87), 113.5 kpc (144), 146.2 kpc (184), and 172.8 kpc (215). Average and median W₀ are respectively shown in filled red and open blue symbols; solid black symbols correspond to upper limits with S/N < 3. Reported values from the literature including low-redshift values (open grey symbols): (Bordoloi et al. 2018; stars), (Borthakur et al. 2015; pentagons), (Liang & Chen 2014; crosses), (Prochaska et al. 2011; diamonds), (Werk et al. 2013; pluses), and high-redshift values (Steidel et al. 2010; black triangles). The error bars correspond to 1σ confidence intervals for average (red filled circles) or median (blue open circles) values based on a bootstrap analysis. Also included are the results from the Kendall-Tau correlation test: the correlation coefficients r_τ and the corresponding p-value (probability of no correlation).